Dr. Xun Zhu and colleagues in Rochestor, Minnesota recently reviewed the medical research that suggests that stem cells can be useful for treating kidney disease. In their review, they focused on the value of mesenchymal stem cells (MSCs), which are a type of stem cell that can turn into a number of different cell types, including bone cells, muscle cells, fat cells, and cartilage cells. MSCs have become a popular type of stem cell for therapeutic purposes for several reasons. First, they can be collected in large numbers with relative ease from places like fat tissue or bone marrow. Second, they fight inflammation, thereby reducing problematic symptoms associated with a number of diseases and conditions. Finally, MSCs seem to work along a number of different pathways that contribute to disease.
In their review, Zhu and colleagues discussed how MSCs are promising specifically within the realm of kidney disease. Both acute kidney ischemia and chronic ischemic kidney disease may be improved with MSCs and currently lack other highly effective treatment options. In addition to their anti-inflammatory properties, which can both protect and repair the kidney, MSCs also seem able to repair the kidney by releasing chemicals called cytokines. Cytokines are cells that are normally secreted by the immune system and impact other cells in ways that are important for healthy functioning.
Pre-clinical research into how MSCs may be used to address kidney disease has been promising. For instance, in a study where rat kidney transplants were being rejected by the rats’ immune systems, MSCs helped reduce the inflammation caused by the immune systems’ reactions. Similarly, in a phase II clinical trial, MSCs reduced the incidence of kidney transplant rejection in human patients. In a separate phase I clinical trial, patients who had undergone heart surgery were given injections of MSCs derived from bone marrow and as a result, were 20% less likely to suffer from acute kidney ischemia postoperatively. Further, the length of hospital stays and the readmissions rates were reduced in this group by 40%.
Researchers have also begun to consider the impact of MSCs on diabetic nephropathy, a progressive disease of the kidney that can occur in diabetes patients. Their pre-clinical studies have shown that MSCs can minimize diabetic nephropathy in rats by lowering inflammation.
The work compiled by Zhu and colleagues demonstrates that significant value that MSCs bring to treating several forms of kidney disease. Going forward, researchers will aim to determine the best route of MSC delivery for each type of disease and how long the effect of MSCs can last.